The sky of the Black Prison World has clouds, black in color, heavy in atmosphere, and boundless in shape, covering every corner of the entire world and sky.
Then on this day.
First, the black clouds in the southeast corner were torn by a white rainbow.
Later, many white spots appeared in the clouds over the Black Prison Castle.
Those white spots were initially tiny, like grains of rice, scattered throughout the clouds as if black ebony had been eroded by white ants. Little black spherical beads squeezed out of those eroded holes, one after another, like drops of black rain, falling into the Black Prison World. They then stretched out, transformed into fierce, monstrous insects, attacking the outer defenses.
